This invention relates to covers to prevent surfaces from being contaminated. The invention particularly relates to shields for sight containers such as glass oilers or sump jugs.
Glass oilers and the like store and supply oil to portions of machinery requiring lubrication and provide a visual indication of the oil condition. Sump bottles or jugs in contrast are connected to a sump or reservoir of oil to provide a visual indication of the oil condition. These sight containers are periodically inspected to determine whether or not the oil is contaminated or changed in condition by a malfunction. Either may ultimately cause machine failure.
Sight containers are often found in industrial settings which include a plethora of contaminants. Perhaps the more severe duty is in atmospheres where free caustic or corrosive vapors are present in the air. These vapors can over a period of time clog or even etch the glass or transparent portions of the sight containers and necessitate their replacement in relatively short periods of time. At present, the machinery attendees periodically attempt to maintain the cleanliness of the sight container surfaces as often as once a week. Despite frequent cleaning, the transparent portion of the sight container must be replaced in as little time as a year in some operations.
A variety of doors or covers for gauges appears in the patent literature to include the following.
U.S. Pat. No. 1,629,328 to Ludwin, et al. for a GAUGEGLASS AND FEED GLASS PROTECTION describes a transparent cover for sight gauges, the purpose of which is to contain broken glass should the gauge shatter.
U.S. Pat. No. 1,273,103 to Sanders for a LIQUID MEASURING TANK discloses a pair of doors 16, operated by a worm gear, which covers the sight gage.
U.S. Pat. No. 1,206,740 to Thaxton describes a MEASURING PUMP ATTACHMENT including gauge doors 25.